How does a treaty come about?

Treaties are international legal agreements which are usually concluded in writing between States or other subjects of international law with a view to regulating their mutual relationships, irrespective of the name given to it, such as treaty, agreement, convention, or protocol.

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Treaties are international legal agreements that are usually concluded in written form between States and/or other subjects of international law in order to agree on mutual relations, regardless of the name of the document (treaty, agreement, arrangement, protocol).

During the last decades, the intensive development of international relations has led to an explosion of treaties, both in the bilateral and multilateral sectors.

Treaties are the main source of international law and give legal form to mutual relations between states.

Belgium’s structure as a federal state and the fact that the Communities and the Regions have been granted authority in international affairs, including the “ius tractati” (the right to conclude treaties), have important consequences for the conclusion of treaties. Depending on the distribution of competencies between the federal government and the federate entities, a distinction is made between exclusively federal treaties, treaties which exclusively concern the Communities and Regions and mixed treaties.

The conclusion of a treaty comprises different steps:

  1. the negotiations;
  2. the signing;
  3. the parliamentary accession;
  4. the ratification;
  5. the publication and the registration.

The negotiations

Multilateral treaties require full negotiating powers, also known as credentials. That kind of authorisation allows the Belgian delegation to participate during the course of a diplomatic conference, to vote and, if necessary, to adopt the texts that were agreed upon at the conference.

The signing

The signing of the text of a treaty means that it is established as authentic and definitive, and it can no longer be modified. Most of the treaties are authenticated by signature. A treaty can only be signed when the signatory/ies is (are) in possession of the necessary full powers granted by the holder(s) of the “ius tractati".

For exclusively federal treaties, the King grants full powers in the form of a special Royal Decree. The Prime Minister and the Minister for Foreign Affairs have permanent full powers, as prescribed in the Vienna Convention on the Law of Treaties.

For community or regional treaties, the head of the community and the regional government is the holder of the "ius tractati". He/she can personally sign a treaty or grant full powers to a representative that he/she appoints.

Parliamentary accession

All treaties concluded by the King must be acceded to by means of a law of accession. All the treaties concluded by the community and regional governments must be acceded to by the respective parliaments. Mixed treaties must be acceded to by all legislative powers concerned.

The ratification

To be bound at the international level, the treaty must be ratified by the King. The instrument of ratification is exchanged with the other party or is deposited with the depositary. The King can only ratify mixed treaties after the federal Parliament and all the competent federate parliaments have given their approval.

Publication and registration

The law of accession and the text of the treaty are published in the Belgian Official Journal (Moniteur belge/Belgisch Staatsblad). In accordance with the Vienna Convention on the Law of Treaties, the text of the treaty must also be registered with the General Secretariat of the United Nations.